Transmission



P. ORR ET AL Nov. 10, 1953 TRANSMISSION 7 Sheets-Sheet 1 Filed Dec. 22,1947 and: 5101' i fnz/ ni o 719'" Pa 1772,27" Orr" P. ORR ET AL Nov. 10,1953 TRANSMISSION 7 Sheets-Sheet 2 Filed Dec. 22, 1947 P. ORR ET ALTRANSMISSION 7 Sheets-Sheet 3 Filed Dec. 22, 1947 P. ORR ET AL Nov. 10,1953 TRANSMISSION 7 Sheets-Sheet 4 Filed Dec. 22, 1947 7 Sheets-Sheet 5v 6Z7LCZI m/lMZ Y/ [ml/8712 0, Palmer -07-7- f TRANSMISSION P. ORR ET ALNov. 10, 1953 Filed Dec.

P. ORR ET AL TRANSMISSION 7 Sheets-Sheet 6 Filed Dec. 22, 1947 III I IIIammwI IRm I fnz/eni ors" Pa Zmer' '0 r7" RmmQI Im u I I I I I (k wash?T0 BRA KE CYL W0 ER 106 and P. ORR ET AL Nov. 10, 1953 TRANSMISSION 7Sheets-Sheet '7 Filed Dec. 22, 1947 Di 0% bo Patented Nov. 10, 1953TRANSMISSION Palmer Orr and Clifford L. Swift, Muncie, Ind.,

assignors to Borg-Warner Corporation, Ohicago, 111., a corporation ofIllinois Application December 22, 1947, Serial No. 793,098

16 Claims.

Our invention relates to transmissions particularly for automotivevehicles and more specifically to arrangements for controlling suchtransmissions.

It is an object of the present invention to provide an improvedtransmission controlling mechanism which is under the influence of theaccelerator of the vehicle such that a power train is completed throughthe transmission when the accelerator is depressed from a closedthrottle position toward an open throttle position. More particularly itis an object to provide such a transmission controlling mechanismadapted for use with a transmission having a hydrodynamic couplingdevice driven by the driving shaft of the transmission and whichnormally has a drag torque, and to this end it is an object to provide afriction engaging means so arranged that on engagement thereof itcompletes the power train through the transmission including thehydrodynamic coupling device, with the friction engaging means beingunder the control of the accelerator to be engaged when the acceleratoris moved to an open throttle position.

It is another object of the invention to provide such a transmissioncontrolling arrangement which includes a governor responsive to thespeed of the driven shaft and which is so arranged that it causes thefriction engaging means 'for completing the drive through thetransmission as aforesaid to be released when the accelerator is movedto a closed throttle .position and below a predetermined speed of thetransmission driven shaft whereby below this speed the vehicle will runfree of the engine and. the hydraulic drag of the hydrodynamic device isnot transmitted to the wheels of the vehicle.

It is a further object of the invention to provide such a frictionengaging means as aforesaid which is engaged by spring pressure and isdisengaged by hydraulic pressure so that when hydraulic pressure is notavailable as when the vehicle is stationary and the engine isinoperative, the transmission may nevertheless be put into gear.

It is also a further object of the invention to provide an improvedhydraulic controlling system in such a transmission control arrangementfor providing not only the necessary fluid under pressure for suchcontrolling but also for supplying appropriate fluid pressure to thehydrodynamic coupling device.

The invention consists of the novel constructions, arrangements anddevices to be hereinafter described and claimed for carrying out theabove stated objects and such other objects as will appear from adetailed description of a preferred embodiment illustrated in theaccompanying drawings wherein:

Fig. l is a longitudinal sectional view, partly schematic, of atransmission embodying the principles of the invention;

Fig. 1A is a fragmentary longitudinal sectional view on an enlargedscale of certain clutch structure illustrated in Fig. 1;

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 1;

Fig. 4 is a partial side elevation of the transmission taken on line 44of Fig. 2;

Fig. 5 is a partial sectional view of the transmission taken on line 55of Fig. 2;

Fig. 6 is a sectional view taken on line 66 of Fig. 2;

Figs. '7 to 12 are sectional views through valve mechanism of thetransmission with the individual valves being shown in differentpositions;

Fig. 13 is a schematic illustration of the hydraulic system of thetransmission control arrangement; and

Fig. 14 is a schematic illustration of the electrical control system forthe transmission control arrangement.

Like characters of reference designate like parts in the several views.

Referring now to the drawings, the illustrated transmission comprises aninput shaft it, an output shaft ll, an intermediate shaft 12 and asecond intermediate shaft IS. The shaft [2 is driven by means of ahydrodynamic torque converter I 4 which in turn is driven by planetaryspeed-up gearing l5 connected with the input shaft H]. The intermediateshaft i3 is splined within the shaft l2 as shown and is;

constructed to connect with elements of a planetary type gear set Itwhich is connected to drive the output shaft l I.

The torque converter 14 is of an ordinary type and comprises an impellerH, a runner I8 and a stator l9. All three of the elements ll, 18 and [9are within a common casing in which there is a quantity of fluid such asoil with the arrangement being such that when the impeller ll isrotated, the runner is is driven at an increased torque and the statorI9 functions as the reaction member of the torque converter. The statorI9 is coupled with the casing 20 of the transmission by means of aone-way brake 20a which functions to allow a free rotation of the statorI9 in the forward direction, that is, in the same direction as thedirection of rotation of the shaft II] but prevents its rotation in thereverse direction. The runner I8 is connected with the shaft I2 as shownand this shaft functions as the driven shaft of the torque converter.

The planetary gear set I5 comprises a ring gear 2|, a sun gear 22, a setof planet gears 23 (one being shown in the drawing) in mesh with thering gear and a set of planet gears 24 (one being shown in the drawing)in mesh both with the sun gear and with the planet gears 23. The ringgear 2| is connected with the input shaft ID; the sun gear 22 isconnected with the shaft I2 and the planet gears 23 and 24 are disposedon a planet gear carrier 25 which is connected with the impeller I! ofthe hydrodynamic coupling device. A one-way roller clutch |2a isprovided between the intermediate shaft I2 and the input shaft II], andthis clutch is so constructed as to engage when the'drive is such thatthe intermediate shaft tends to drive the input shaft in the forwarddirection, or in the same direction as these two shafts are driven bythe engine of the vehicle.

The planetary gear set I5 functions to drive the carrier 25 and therebythe impeller I! at a speed greater than that of the input shaft I whenthe shaft I2 driven by the converter is stationary. As the runner I8 andthe shaft I2 increase in speed of rotation, the speeds of the carrier 25and the impeller I'I decrease with respect to the speed of the shaft I0,and presently all of the parts of the planetary gear set I and thetorque converter I4 rotate substantially at the same speed as the inputshaft II). The stator I9 is held stationary by the one-way brake 2011when torque is being multiplied through the converter I4, and theone-way brake allows the stator to rotate freely in the forwarddirection after the converter begins to function as a simple fluidcoupling at which time there is no multiplication of torque. The one-wayclutch I2a functions so that the shaft I2 may drive the shaft ID, aswhen the vehicle is coasting, so that the drive need not go through thetorque converter I4 with the attendant slip.

This particular arrangement of torque converter and planetary speed-upgearing is shown only diagrammatically in view of the fact that theconstruction is well-known in the prior art being shown, for example, inSchneider Patent No. 2,333,681.

The planetary gear set I6 comprises a ring gear 26 which is fixed to theoutput shaft II, a sun gear 21, a set of elongated planet gears 28 inmesh with the sun and ring gears (one gear 28 being shown in thedrawing), a set of elongated planet gears 29 each of which is in meshwith one of the gears 28 (only one of the gears 29 being shown in thedrawing), a sun gear 30 in mesh with the gears 29 and a carrier 3| forthe planet gears 28 and 29. A brake drum 32 is connected with thecarrier 3|, and a friction brake 33 is provided for braking the drum andthereby the gear carrier.

The intermediate shaft I3 is splined within the shaft I2 as shown andhas fixed thereto a control rod 34 which extends through a suitable slot35 within the shaft I2. The rod 34 carries a collar member 36 providedwith a channel 31 therein for receiving a suitable fork whereby the 4member 36, the rod 34 and thereby the shaft I3 may be shifted.

The shaft I2 is rotatably disposed within the transmission case by meansof a ball bearing 38 and the output shaft is rotatably disposed withinthe case by means of a ball bearing 39. The shaft I3 is rotatablydisposed within shaft II by means of a needle bearing 40; the carrier 3|is rotatably disposed on the shaft II by means of a bearing 4|; and thecarrier is rotatably disposed with respect to the intermediate shaft I2by means of a bearing 42.

The intermediate shaft I3 is formed with external clutch teeth 43 and44. The sun gear 21 is provided with internal clutch teeth 45 and thesun gear 30 is provided with internal clutch teeth 46. The carrier 3| isformed with internal clutch teeth 41, and a blocker type synchronizerring 48 disposed within the carrier 3| as shown is provided with blockerteeth 49. As shown in Fig. 1A, the ring 48 is provided with lugs 4311which extends into slots 39a in the gear 30. The slots allow the ring alimited rotation with respect to the gear and at the limits of itsmovement, the blocking teeth 49 are out of line with the teeth 46 on thegear 30. A spring 48b is provided between the ring 48 and the gear 30for holding the ring in engagement with the carrier 3|. The copendingapplication of Palmer Orr, Serial No. 793,097, filed December 22, 1947,now Patent 2,560,886, may be referred to for a more detailed descriptionof the synchronizer ring 48 and associated parts, as well as for adescription of the transmission so far described.

The shaft I3 is movable longitudinally with respect to the transmissioncasing 20 and. with respect to the shafts I2 and I I. The clutch teeth44 by movement of the shaft I3 to the rear mesh with the teeth 45, andthe teeth 44 and 45 thus constitute a positive clutch for connecting theshaft I3 with the sun gear 21. The teeth 43 on the shaft I3 are adaptedto mesh with the teeth 46, and the teeth 43 and 46 thus constitute apositive type clutch for connecting the sun gear 30 with the shaft I3.The teeth 43, when the shaft I3 is moved farther forwardly, are adaptedto mesh also with the teeth 41 on the carrier 3|, while at the same timeremaining in mesh with the teeth 46. In this case, the shaft I3 isconnected both with the sun gear 30 as well as with the carrier 3|. Thesynchronizer ring 48, when the teeth 43 abut against the teeth 49thereon, functions to synchronize the carrier with the shaft I3 and whensynchronism is attained, the blocker synchronizer 48 rotates slightlywith respect to the teeth 43 and allows the latter teeth to come intoengagement with the teeth 41.

In the operation of the illustrated transmission, which is assumed. tobe installed in an automotive vehicle as the transmission isparticularly adapted. for use in such a vehicle, the input shaft I8 isdriven by means of the engine (not shown) of the vehicle, and the outputshaft II is connected with the road wheels of the vehicle and drive thesame through the suitable connections (not shown). When the input shaftI0 is rotated, the impeller H of the torque converter I4 is driven at anincreased speed with respect to the shaft I0 and applies torque on therunner I8 of the torque converter and thereby on the shaft I2. The shaftI3 together with its shift collar 36 are assumed to be in the positionsin which they are shown, namely, in their neutral positions, with theteeth 43 and 44 being out of mesh with any of the other teeth in thetransmission, and the friction brake 33 is released from the drum 32.The shaft I3 rotates freely within the gear set and there is no drivebetween the shaft l2 and the shaft H.

The transmission is conditioned for low speed forward drive by engagingthe teeth 43 with the teeth it by moving the shaft I3 forwardly of thetransmission. The teeth 43 and 46 may be engaged with a minimum of clashdue to the fact that the friction brake 33 is disengaged and it isnecessary for the clutch teeth to pick up only the frictional andinertia loads of the parts in the gear set. With the teeth 43 and 46engaged, the low speed forward drive train through the transmission maybe completed gradually by a gradual engagement of the friction band 33.In this case the sun gear 353 is driven by means of the shafts i2 and I3and the drive is through the planet gears 28 and 2b to the ring gear 25and thereby to the output shaft l l. The planet gear carrier 3| is heldstationary by means of the band 33, and the carrier 3| functions as thereaction member of the gear set.

In order to shift from low speed forward drive to high speed or directdrive in the gear set, the shaft i3 is shifted by means of its shiftcollar 3t forwardly to bring the teeth t3 into mesh also with the teeth4? in addition to the teeth 46. With the teeth as being in mesh withboth the teeth 4.6 and ll, the shaft I3 is coupled to both the carrier3! as well as the sun gear 39. It will be understood that as this shiftof the shaft [3 is made, the friction brake 33 is released. Coupling ofboth the sun gear 36 and carrier 35 to the shaft l3 causes a lock up ofthe parts of the gear set so that all of them rotate together and 1-1drive results between the shafts i2 and l i It will be understood thatin both low speed forward drive and in direct drive through the gear setit, the hydrodynamic coupling ll transmits the torque as is required bythe road wheels of the vehicle and the relation of the speeds betweenthe impeller and drive shaft it varies in accordance with the load onthe output shaft H in either of the speed ratios.

As has been described, the teeth 49 function to prevent a movement ofthe shaft IE to bring its teeth t3 into engagement with the teeth lluntil there is a synchronization between the teeth 43 and M. Thissynchronization is obtained by interrupting the drive between the shaftsl8 and H, as by decreasing the speed of the engine of the vehicle so asto allow synchronization in speed of the parts i3 and (ii. Thesynchronizer ring 533 also functions to hasten this synchronizing sothat the teeth 43 may move through the teeth 59 to engage with the teethiii.

A drive in reverse may be obtained through the transmission by movingthe shaft I3 rearwardly out of its neutral position in which it is shownto mesh the teeth 44 with the teeth 45. The engagement of these teeth isaccomplished similarly to that of the teeth it and it, namely, with theband 33 disengaged, and after the transmission has been conditioned forreverse by engagement of these teeth, the band 33 is engaged to completethe drive through the gear set and thereby through the transmission. Theshaft l 3 is driven from the shaft i2 and rotates the sun gear 2'? inthe forward direction. The band 33 functions to hold the carrier 3istationary, and the ring gear 26 is thereby rotated in the reversedirection to give reverse drive through the transmission.

The transmission just described in detail is intended to be controlledautomatically in accordance with actuation of the vehicle accelerator,and the transmission controls will now be described. The two parts ofthe transmission controlled are the brake band 33 and the shift collar36. The brake band 33 is controlled by means of a fluid cylinder 5i]fixed with respect to the casing 20 of the transmission and linkagemechanism 5! connecting the cylinder and brake band. The cylinder 50contains springs 52, 53 and 5-3 acting between the end of the cylinderand a piston 55 within the cylinder. The piston is fixed on a piston rod5%. The linkage mechanism 55 comprises a lever 51 acting on a pin 58which is pivotally mounted to one end 3311 of the brake band 33. Theconnection between the lever 5! and pin 53 is eccentric with respect tothe point of rotation of the link 5? so that when the link 5? is rotatedin the counterclockwise direction as seen in Fig. 3, the pin 58 and theend 33a of the band 33 are moved upwardly to tighten the band. The otherend 332; of the band 33 is fixed with respect to the transmission casingby means of an adjustable stud 59. It will be noted that the springs 52,53 and 5% act on the piston 55 and rod 55 so as to hold the lever 51 inits band engaging position, and, as will be described, the band isdisengaged by application of pressure to the piston 55.

The collar 35 is shifted by means of a fork 63 extending into thechannel 37! of the collar and fixed on a shift rail 6! slidably mountedin the transmission casing 20. The shift rail 8| may be shifted by meansof a shift lever 62 on the outside of the transmission swingably mountedby means of a shaft 553 extending through the transmission case. Theshaft 63 has fixed to it on its inner end a lever 6 5 which is disposedand works in a slot 65 in the shift rail (ii A lever E6 is also disposedon the shaft t3 and is freely mounted on the shaft. The lever 65 isprovided with two oppositely disposed cammed slots 67, and the lever 66'is provided with two face cams 58 which engage in the slots 67. Thelever (it is held against the cams 68 by means of a spring 69 disposedbetween the lever 66 and the casing 29, and the rail 5| has a slot illfor receiving the lever 65.

The shift rail 6i has four positions, namely, for reverse, neutral, lowspeed forward and high speed forward ratios of the gear set, and foreach of these ratios a slot is provided in the rail, the slots beingdesignated respectively as M, i2, i3 and M. A poppet ball "i5 isprovided in a suitable opening in the transmission casing, and this ballis acted on by a spring it. The ball is adapted to enter the slots H i2,i3 and it for yieldably holding the shift rail in any of its fourpositions.

The lever 6A} is provided with a sector ii and a poppet comprising aball 78 and a spring 19 pressing on the ball acts on this sector. Thespring and ball are disposed within a suitable cylindrical cavity formedin the transmission casing. The sector H is provided with a notch Bilfor receiving the ball in one of the positions of the lever fi l. Thelever 51?. is acted on by a pin 8i fixed within the transmission casingwhich functions as will be described to hold the lever from longitudinalmovement along the shaft 63 due to action of the cams 68 until the shafthas rotated a predetermined amount. The lever 65 is also acted on by apin 82 which functions to stop rotative movement after the lever 56 hasmoved a certain amount.

The shift rail 6! is adapted to be shifted also 7 by a lever 83 which isfixed to a shaft 84 rotatably disposed in the transmission casing. Theshaft 84 has fixed on its outer end. a lever 85. The lever 83 is adaptedto engage in a slot 88 in the shift fork 60 which is fixed to the shiftrail ti.

The brake 33 by means of the brake-operating piston 55 is controlled bymeans of a fluid pressure system (see Fig. 13). This system comprises afluid pressure pump 81 which is driven by the impeller ll of the torqueconverter I I by means of gears 88 and. 89. The pressure pump is connected with an oil tank 99 and supplies fluid under pressure to a valveassembly 9 I. The pressure supplied by the pump 81 is kept at somepredetermined value by means of an accumulator and high pressure reliefvalve 92. The relief valve 92 comprises a piston 93 movable in acylinder 94 formed within the transmission casing. The piston is actedon by a pair of springs 95 and 96, and the cylinder is provided with arelief outlet 9'] which is opened by the piston when it moves in thecylinder.

The relief outlet 9'! is connected with a second relief valve 98 andalso with the torque converter I I. The relief valve 98 comprises apiston 99 movable within a cylinder I03 against the action of a spring IM. The cylinder I03 has a relief opening I02 which is connected withparts hereinafter to be described. The connection of the relief opening91 with the converter I4 is with the housing of the converter Ida (seethe diagrammatic showing of the hydraulic system) in which the threeelements I7, I8 and 69 are disposed and which holds the fluid for thethree elements. The relief opening 9! is also connected with an internalpassage I63 within the intermediate shaft I3 for lubricating thetransmission.

The hydraulic system includes also a scavenger pump I04 which is drivenby the gear 8-5 and also by a gear I05 in mesh with the gear 88. Thepump IE4 is connected with the transmission casing 29 for taking thefluid which leaks from the gear set and from the torque converter andputting it back into the system. The pump I04 discharges into the oiltank 90 as shown. The relief valve 98 functions to maintain the fluidpressure within the housing Me of the torque converter and within thepassage I 03 of the gear set at a predetermined value and the dischargefrom this relief valve is to the inlet side of the scavenger pump I04.

The valve assembly 9| comprises a valve body I06 fixed with respect tothe transmission casing 20 and three valves I01, I08 and I09 slidab'lydisposed therein. These valves are slidably disposed respectively incylinders H0, III and II2 formed in the valve casing I05. The cylinderH0 is connected by passages H3 and H4 with the cylinder II I and isconnected by means of the latter pas sage also with the accumulator orhigh pressure relief valve 92. The cylinder III! also has a dischargeopening II5. The cylinder III is con nected by means of passages IIS andIII with the cylinder H2, and the latter cylinder is connected bypassages H8 and H9 with the brake cylinder 50.

The valve I0! is provided with an elongated groove I20; the valve I03 isprovided with two spaced grooves I2I and I22 and the valve I09 isprovided with an elongated groove I23 and a groove I24 which is shorterin length.

The three valves I01, I08 and I09 are connected with various mechanismsfor moving the valves. The valve I0! is provided with a slot I25,

and a pin I26 (see Fig. 6) carried by a lever I21 is disposed in thegroove. The lever I2? is oscillatable with respect to the transmissioncasing, being carried by a shaft I28 fixed to the casing. The lever I2!is oscillated by means of a lever !29 which has a pin I30 entering intoa slot I3I Within the lever I21. The lever I29 is fixed on a shaft I32rotatably mounted in the transmission casing, and a lever I33 (see Fig.2) is fixed on the outer end of the shaft I 32 for the purpose ofoperating the lever I29.

The valve I03 is provided with a slot I34, and an armature I35 (see Fig.6) of an electric solenoid I30 fits within the slot I34 so that thevalve and armature are connected for movement together. The solenoid I35 includes a spring I 31 which acts to move the armature I35 to itsoutermost position with respect to the solenoid and thereby yieldablyholds the valve I08 in a corresponding position.

The valve Ii'iEI is connected to be moved in accordance with movementsof the lever 6d which shifts the shift rail 5|. The valve I99 isprovided with a groove I38, and a pin I239 carried by a lever I40extends into the slot. The lever I40 is oscillatively mounted on a shaftMl carried by the transmission and this lever has a rod I62 connectedtherewith. The rod is slidably disposed with respect to the transmissioncasing 2c and is carried by two perforated lugs I 33 formed on thecasing. The rod I 32 is in contact with a sector I ii formed on theshift lever and this sector is formed with a slot I 35 adapted toreceive the end of the rod I42 when the lever 6:2 is moved to apredetermined rotative position. A spring H35 is provided between one ofthe lugs I63 and a collar I i'i fixed on the shaft I 32 for the purposeof holding the end of the rod M2 against the sector M2.

The lever is operated by a vacuum motor I43. This motor includes adiaphragm it!) connected to a piston rod I50, and the end of the pistonrod is adapted to abut against the end of the lever 85. A spring I5I isprovided for acting on the piston rod for holding it normally in itsoutermost position, and when vacuum is applied to the vacuum motor, itpulls the rod. tile into the motor against the action of the spring 25LA holding coil I 52 is provided within the motor for holding the pistonrod I53 at its innermost position against the action of the spring I5I,after vacuum has been utilized for drawing the piston rod into itsinnermost position. A spring I53 is provided between the transmissioncasing and the lever 85 for rotating the lever after the piston rod hasbeen moved to its innermost position within the vacuum motor.

The vacuum motor is connected to an electrically operated vacuum valveI54. The valve includes a valve piston I55 connected with an armatureI56 of an electro-magnet I57. The valve comprises a casing I58 having aport I59 open to atmosphere and a port I65 connected with a source ofvacuum I5! which may be the manifold of an ordinary internal combustionenbine used for driving the vehicle in which the transmission isinstalled. The electro-magnet when energized causes upward movement ofthe armature I56 and piston I E5 to close the port I59 and open the portI39 and these ports are respectively opened and closed as will beapparent when the electro-rnagnet is deenergized.

The lever 62 is connected by any suitable linkage with a shift lever I52located within easy reach of the driver of the automobile, such asimmediately beneath the steering wheel I63 of the vehicle. This linkagemay comprise a link i534 connected with the lever 62 on one end and withanother lever I65 on the other end. The lever I65 is connected with thelever I62 by a shaft I66 so that rotative movement of the lever I62causes similar rotative movement of the lever I65.

The lever I33 is adapted to be accelerator controlled and is connectedwith the accelerator I-Bl of the vehicle. The accelerator I61 functionsin the usual manner for opening the throttle I68 of the vehicle and maybe connected with the lever H33 in any suitable manner as by a link I69.

The electrical controls for the transmission comprise the holding coil62 in the vacuum motor I68, the vacuum valve I56 having an electricsolenoid I51 and the electric solenoid I36 hereinbefore described. Thevacuum motor I66 includes an electric switch having contacts I18 and IllI. The solenoid I36 includes an energizing winding H2 and a holding coilIl3 and also includes a switch having contacts Il i and I15.

The electrical control system includes also steering column switches I16and Ill which are closed for various positions of the levers I62 and 62.These switches include respectively contacts H8 and contacts Il9. Twoaccelerator control switches I86 and I8I are also provided, and theswitch I89 includes contacts I82 and I83 and the switch I8! includescontacts I84. A rail switch W5 is provided which includes contacts I86and I8l, and this switch is actuated by the rail 6| or more particularlyby the shift lever 66 attached to this rail. The electrical circuitincludes also a switch I88 operated by a governor I89 driven from theoutput shaft I I.

The electrical system includes a relay I90 comprising a winding I9i forcausing movement when energized of an armature I92. Two sets of contactsI93 and I94 are closed upon movement of the armature I92 due toenergization of the coil IHI.

The electrical system is connected with the usual battery I95 andignition switch I96 of the vehicle and is also connected with theordinary ignition system of the vehicle I9l comprising the ignition coilhaving a primary winding I98 and a secondary winding I99 and aninterrupter 280 for current through the primary winding.

As is shown, the switches I96, I16, I8I, I88 and the contacts I62 ofswitch I89 are connected in a series circuit with the relay winding I9!and the battery I95. The contacts I93 of the relay I98 connect theswitch Il6 with the contacts I8l of the switch I85 and thereby with theignition switch I96. The contacts I94 connect the switch ll6 with theswitch Ill, the vacuum valve I54 and the winding I62 of the vacuum motorM8. The contacts H9 and HI in the vacuum motor are connected with thecontacts I83 of the switch I89 and thereby with the primary winding I96of the ignition system. As will be noted the contacts E86 of the switchI85 are in parallel with the switch I8I.

As has been described, the transmission provides a low forward drive, adirect drive, a reverse drive and a neutral condition, all of the drivesincluding the torque converter I l, and shifting between the variousdrives is accomplished by operating the shift collar 36 and the brakeband 33. The shift collar 36 is actuated primarily by the lever I62beneath the steering wheel I63 which lever actuates the shift lever 62on the side of the transmission. The shift lever 62 and thereby theoperators shift lever I 62 have four definite positions which correspondto reverse drive, neutral, low speed forward drive and automatic highdrive, all of these positions being indicated in the drawings withrespect to the lever 62. If the levers I62 and 62 are moved to their lowspeed positions, the levers 66 and 66 are thereby moved in the samemanner as lever 62 since they are connected with this lever. Althoughthe lever 66 is rotatably mounted on the shaft 63, it nevertheless moveswith the lever 64 due to the fact that the pin 8| holds the lever 66from axial movement along the shaft 63 which would be caused by the cams68. The lever 66 fitting in the smaller slot 18 in the shift rail 6Ithus functions to move the shift rail 6| to the left as seen in Fig. 6,so that the ball 15 moves into the slot l3. The shift fork 60 moves withthe rail 6i, and the shaft I3 is shifted to the left as seen in Fig. l,to mesh the teeth 43 with the teeth 46 for conditioning the low speedpower train for completion. The band 33 is disengaged and the teeth 43may be meshed with the teeth 46 without difficulty since, if the partsare rotating at all, they need only be brought to the same speed againstthe forces of inertia of the parts. This engagement of the teeth 43 withthe teeth 46 will result in the planet gear carrier 3| being driven inthe reverse direction until the throttle I69 is opened.

With the transmission being conditioned for neutral, the vehiclestationary and the throttle closed, the valves are in the conditions inwhich they are shown in Fig. '7. Conditioning of the transmission forlow speed forward drive as has just been described has the effect ofmoving the valve E69 from its position as illustrated in the formerfigure to the position in which it is illustrated in Fig. 10, and thelatter figure illustrates the positions of the valves when thetransmission is conditioned for low speed forward drive and before theaccelerator I6l is depressed to open the throttle. The lever 66 isrotated by movement of the levers 62 and I62 when the transmission isconditioned for low speed forward drive, and movement of the lever 69brings it to a position in which the link I62 enters the notch I45 inthe sector Hi l of this lever. The spring I46 is operative to move thelink into the notch, and this movement of the link has the effect ofrotating the lever I96 and thus moving the valve I09 into the positionin which it is illustrated in Fig. 10 from its position in which it isillustrated in Fig. 7.

While the throttle remains in closed condition with the transmissionbeing thus conditioned for low speed forward drive, the valves Itl, I88and I89 are in the conditions in which they are shown in Fig. 10. Thepassage H4, to which fluid under pressure is supplied as will behereinafter described, is in communication with the brake cylinder 59through the groove I26, the passage I IS, the groove i22, the passageII6, the groove I23 and the passage H8, and fluid under pressure is thusapplied to the piston 55 for the brake 33. The springs 52, 93 and 54normally hold the brake engaged but when fluid under pressure is appliedto this piston, the piston moves inwardly of the cylinder 69 anddisengages the brake. Thus with the throttle in closed con- 1( Jiitionthe brake 33 is held in disengaged condi- Referring to the diagrammaticillustration of the fluid system in the transmission, fluid underpressure is supplied to the port H4 in the valve block I06 from theaccumulator or high pressure relief valve 92, being supplied by thepressure pump 81 driven from the impeller IT. The pump is directlyconnected with the passage ii and the pressure discharged by the pump iskept at a certain value due to the action of the relief valve 82, thepiston 93 moving back within the cylinder 94 against the springs 95 and96 to open the relief port 9'! when the pressure discharged by the pump81 increases above this value. The fluid discharged from the reliefpassage 9'! goes to fill the hydrodynamic device I 4 and also isconnected to discharge into the passage I93 in the shaft I3 forlubricating the transmission. This pressure is kept at somepredetermined lower value by means of the relief valve 98 having apiston 99 functioning similarly to the piston 83 to open a relief portI02 when the pressure of fluid applied to the turbine increases beyondthe lower predetermined value. The fluid discharged through the orificeI02 is connected with the inlet side of the scavenger pump I84 which notonly pumps this fluid back into the oil tank 98 but also functions topump the fluid from the casing 20 into the oil tank 90. It will benoted, incidentally, that the inner ends of the cylinders 94 and 98 arevented to the transmission casing 20 so that any fluid leaking past thepistons 93 and 99 goes within the transmission casing where it is drawnoff by means of the scavenger pump I04.

As the throttle is opened, with the transmission being conditioned forlow speed forward drive, the positions of the Valves are as shown inFig. 11. The throttle valve I! is moved from its closed throttleposition to an open throttle position thereby taking the groove I28 outof communication with the fluid supply passage I I4 and connecting thepassage II3 with the discharge opening I I5. The brake cylinder 50 isthus drained of fluid and the springs 52, 53 and 54 become operative toengage the brake 33 through the linkage comprising the lever 51 and thelink 58. The low speed forward ratio through the transmission is thuscompleted.

The valve I 6? is moved from its closed throttle position to an openthrottle position by means of the lever I33 on the outside of thetransmission actuated by the accelerator I67. When this lever is movedfrom its closed throttle position to an open throttle position which maybe less than the wide open throttle position, the valve I0! is movedbetween its two positions just mentioned. Swinging movement of the leverI33 causes a corresponding rotation of the lever I29 carrying the pinI30, and this pin moves within the slot I3I in the lever I2! and swingslever I21 about its shaft I28. The lever I2? is connected by means ofthe pin I 26 with the valve IGTI and this moves the valve. The valve I0!is thus moved to engage the brake 33 when the accelerator it! is movedout of its engine idling position in a throttle opening direction.

Ihe shape of the slot I3I is such that the valve I8! is moved betweenits open and closed throttle positions with a small movement of theaccelerator in a throttle opening direction, and for the remainder ofthe movement of the accelerator in the throttle opening direction, thepin i258 simply travels in the slot I3i without causing any movement ofthe lever IN. The valve I8? is returned to its closed throttle positionby a release of the accelerator to its engine idling position, and inthis position the valve I01 again applies fluid pressure to the brakemotor 50 to disengage the brake 33. The drive through the transmissionis thus broken, and the arrangement gives a free wheeling type of driveas is apparent.

The transmission is shifted from the low forward speed condition toautomatic high condition in which the transmission may be automaticallydownshifted from direct drive to low forward speed drive by actuation ofthe accelerator as will be hereinafter described, by actuating the shiftlever I62 and thereby the lever 62, moving the latter to its automatichigh position. This movement of the lever 62 moves lever 64, since bothlevers 62 and 64 are fixed to the shaft 63, and due to the fact that theslot 65 is elongated, this movement of the lever 64 does not affectmovement of the rail 6!. The lever 66 at this time has moved to the stoppin 82 and therefore cannot move radially any farther but the hub ofthis lever has moved past the pin 8|, and the earns 68 operate at thistime to move the lever 66 out of engagement with the rail 6|. The railGI thus remains in its low speed forward position with the ball 15 beingin the notch '13. Movement of the lever 64 to its automatic highposition, it will be noted, moves the pin I42 out of the notch I 45against the action of the spring I46. The pin I42 causes correspondingmovement of the lever we and this moves the valve I89 into its automatichigh position, which is the same position of the valve corresponding toneutral and reverse, such valve position being shown in Fig. 7.

With the throttle being closed at first and then opened, with thetransmission being conditioned for automatic high, the valve I01 movesfrom its condition in which it is shown in Fig. '7 to its position inwhich it is shown in Fig. 8. In Fig. 7 in which the valve I8! is shownin its closed throttle position, the oil supply passage H4 is connectedwith the brake cylinder 50 for disengaging the brake, the movement ofthe valve III! by means of the accelerator I 61 to its open throttleposition as shown in Fig. 8 causes the brake cylinder to be connectedwith the discharge passage II5 in the valve block I06 and the cylinder50 is thus drained and the brake 33 is engaged. With the transmissionbeing thus conditioned for automatic high, opening of the throttle thuscauses a drive in low speed gear.

The drive in low gear forward continues until the driver wishes to gointo high gear and at such time in order to make this shift he simplyreleases the accelerator IB'I allowing it to come back to its closedthrottle position and this shift will be made assuming that the criticalspeed of the governor I89 has been reached. Referring to the electricwiring diagram, it will be noted that the switches ITS, I96, I8I, I andI88 are in series. The switch I76 is actuated by the shift lever I andthereby by the drivers shift lever I 62 so that this switch is closedwhenever the shift lever IE2 is moved to condition the transmission forforward drive, in either low speed forward lockup or for automatic highspeed drive. The ignition switch I96, of course, is on whenever theengine of the vehicle is operative. The switch I BI is a closed throttleswitch and is controlled by the accelerator I61 and is'closed when theaccelerator is in closed throttle position. The switch I80 is a kickdownswitch and is in its condition as shown in the wiring diagram for allpositions of the accelerator except when the accelerator is moved to awide open throttle position, and the governor switch I88 is closedwhenever the speed of the output shaft increases above a predeterminedspeed. When the vehicle speed and thereby the speed of the output shaftli reach predetermined values, the switch 688 closes and the relay E99is energized by means of the series circuit just mentioned, assumingthat the accelerator is moved to its closed throttle position forclosing the switch liil. The contacts i923 and We in the relay areclosed upon energization of the relay.

The switch ill, like the switch H6, is actuated by means of the lever 82and thereby by means of the operators control lever Hi2, and the switchill is so connected as to be closed when the levers t2 and E92 areshifted to condition the transmission for automatic high forward drive.Closure of the contacts i923 has the effect of energizing the solenoidI36 and thereby its windings H2 and lit. Energization of the solenoidhas the effect of pulling the solenoid armature i335 inwardly againstthe action of the spring i3? and thereby moves the connected valve Hi8to its position in which it is shown in Fig. 9. The contacts lid and W5are separated on the armature moving in this manner, since the switchlM-Jlt is actuated by the armature; however, the holding winding H3remains energized and holds the armature i359 in its position within thesolenoid l3ii. With the valve I198 in its solenoid energized position,the oil pressure supply passage ll l is connected by means of the grooveml, the passage ill, the groove E29 and the passage H9 with the brakecylinder 50 for disengaging the brake.

Closure of the contacts i9 5 in the relay E99 has the effect ofenergizing the winding it? of the vacuum valve led and also of theholding winding use in the vacuum motor Hi8. When the winding i5? isenergized, the valve I58 is changed from a condition in whichatmospheric pressure is admitted to the vacuum motor I08 to a conditionin which vacuum from the vacuum line Hil is applied to the diaphragm M9in the vacuum motor its. When vacuum is thus applied to the diaphragmM9, the plunger E50 of the motor M8 is drawn inside the motor and thisallows the spring M3 to be operative to move the lever 85 clockwise asseen in Fig. 4. The lever 93 is connected by means of the shaft 89 withthe lever 85, and therefore the lever 83 moves with the lever 85. As thelever 83 moves, it engages in the slot 98 in the shift fork t and movesthe shift fork and thereby the rail 8i into their high speed positions,with the ball it being positioned. in the notch i i. As the shift forkmoves to the high speed position, the gear 13 slides through theblocking ring 98 and its blocking teeth assuming that the accelerator ispermitted to remain in its throttle closing position a sufficient timefor the parts 3-3, 49 and ii to synchronize. The clutch it being inengagement with the gear 90 and the carrier 3!, the planetary gear setit is locked up and a direct drive results between the intermediateshaft l2 and the output shaft ll has been described and the transmissionis in direct drive.

The rail switch lad is actuated by means of the rail 8! so that when therail El moves into its high speed position with the ball 75 being in thenotch l t, the switch ltd is actuated to close the contacts l8? and E89.Since the contacts ltd are closed, the relay E99 remains energized tokeep the relay contacts I93 and I94 closed even though the acceleratorIt? is moved from its closed throttle position to an open throttleposition as would normally be done when an automobile is being driven.The transmission thus remains in high speed ratio after the shift hasbeen made above the critical speed of the governor I89 when theaccelerator is released temporarily to its closed throttle position. Aswill be noted, the accelerator operated valve I0? may be in either ofits positions corresponding to closed throttle or open throttle andsince the oil pressure does not proceed through this valve to the brakecylinder, the brake piston 55 remains energized to keep the brake indisengaged condition.

The transmission may be downshifted by moving the accelerator to itsopen throttle position so as to actuate the kickdown switch I80. Whenthis switch is actuated, the circuit through the relay I90 is broken andthe relay contacts I93 and I94 open. The solenoid I36 is thusdeenergized and the valve I08 is moved back to its position in which thegroove I22 is in communication with the passages I I3 and H6. Thepositions of the valves I01, I08 and I09 may be then as shown in Fig. 8,and the brake cylinder 50 is drained through the passage II5 to engagethe brake 32. Deenergization of the winding I51 of the vacuum valve I54and of the holding coil I52, due to opening of the contacts I94, has theeffect of permitting the spring I5I of the vacuum motor I48 to beeffective to again move the piston rod I50 and the lever back to theirlow speed positions against the action of the spring I53. The springI5I, however, cannot be effective to move these parts, together with theshift rail GI and the shift collar 60, until the drive from the enginehas been broken in some manner to relieve the thrust between the teeth43 and the teeth 41, and this is done by grounding the ignition circuitfor the engine of the vehicle. The contacts I10 and Ill in the vacuummotor I49 are closed when the lever 85 and the vacuum motor piston I50are in their high speed positions, and these contacts are in series withthe contacts I83 in the kickdown switch I80, and one of the contacts I83is connected with the end of the ignition coil I98 between the coil andthe interrupter 200. The contact I'II in the vacuum motor I08 isgrounded as shown, and when the contacts I19 and Ill are closed and thecontacts I83 are closed on a kickdown by means of the accelerator, theignition coil I98 is grounded so that the engine stops firing, thusinterrupting the power delivered by the engine. The spring I5I is theneffective to move the vacuum motor piston rod I50 and the shift lever 85and thereby the shift rail 6| back into their low speed forward drivepositions.

As has been described, the governor I89 when it closes the governorswitch I88 conditions the mechanism for an upshift by a release of theaccelerator above a predetermined speed of the output shaft II. When thetransmission is conditioned for low speed lockup, the governor and itsswitch has the function of preventing disengagement of the brake band 33when the accelerator is released to its throttle closing position sothat the vehicle coasts against the engine. The movement of theaccelerator controlled valve I01 in starting the vehicle in low lock-upcondition of the operators control lever I62 and the transmissioncontrol lever 62 are shown in Figs. 10 and 11. When the governor I89reaches its critical speed, the governor switch I88 is closed, andassuming the switch I8I is closed at closed throttle position, the relayI90 will be energized, and thereby the solenoid I36 will be energized.En-

ergization of the solenoid I36 has the function of moving the valve I08, such as is shown in Fig. 12, and therefore after the brake cylinder50 has been once drained in driving in low speed forward, oil pressurecannot again be applied to the brake cylinder to release the brake,regardless of the position of the throttle valve I 01, with the valvesI08 and I09 remaining in the positions in which they are illustrated inthis figure. The brake band 33 thus remains engaged and above thecritical speed of the governor I89, the vehicle coasts against theengine.

The transmission is conditioned for reverse drive by moving thetransmission control lever 62 into its position in which it is indicatedfor reverse by means of the operators control lever I62. Movement oflever 82 causes corresponding movement of the lever 64, and this leveracting in its slot 65 in the shift rail 6| causes corresponding movementof the shift rail and the shift fork 60 to shift the shaft I3 to meshits teeth 44 with the teeth 45 of the sun gear 21. The gear set I8 isthus conditioned for reverse. Both of the switches I16 and I11 which arecontrolled by the levers I62 and 62 are open when the transmission isconditioned for reverse. The electric circuits thus are not operative toactuate the vacuum motor I48 or the solenoid I36 or the vacuum valveI54, and the only valve of the valves I01, I08 and I09 that is moved isthe accelerator controlled valve I01. The valve I09 is in the sameposition as for automatic high forward drive and the valve I01 is movedby the accelerator from its position shown in Fig. 7 in which fluidpressure is supplied to brake cylinder 50 to its position in which it isshown in Fig. 8 in which the brake cylinder is drained through passageII to engage the brake. As in forward speed drives below the criticalgovernor speed, the brake is engaged when the accelerator is moved fromits closed throttle position toward an open throttle position and isreleased when the accelerator is returned to its closed throttleposition, thus giving a free-wheeling type of drive.

The transmission and control arrangement therefor hereinabove describedadvantageously provides a low speed power train completed by engagementof the brake 33 under the control of the accelerator of the vehicle. Thebrake 33 is engaged by the springs 52, 53, and 54, and the piston 55acts against the springs to disengage the brake. the fluid motor 50 whenthe accelerator is returned to its closed throttle position, assumingthat the speed of the driven shaft I I is below the critical governorspeed. The reverse drive power train is completed in a similar manner,and the transmission is conditioned for either forward or reverse driveby engagement of the clutch teeth 43 either with the teeth 46 or theteeth 45 of the sun gears 30 and 21, respectively. The same fric tionband 33 advantageously is utilized for either forward or reverse drive.When the transmission is conditioned for low speed lock-up, as when thelever 68 shown in Fig. 6 is put in this position, the governor functionsin this case to prevent a freewheeling type of drive above the criticalgovernor speed. We provide an advantageous system of valves I81, I 88and I 09 for accomplishing these functions under the control of theaccelerator,

the governor, and the selector I82, respectively.

It will be noted that the shaft I3 is shifted into its low and reversepositions by manual effort through the action of the lever 62; however,a motor I48, under the control of the vehicle ac- The acceleratorfunctions to energize celerator, is provided for shifting between thehigh and low speed conditions of the transmission.

We consider an important feature of this transmission the fact that theplanetary brake band 33 is released when the accelerator is in closedthrottle position below the critical governor speed. Thus, with theseconditions existing, the car will free-wheel and when standingsubstantially still, the hydraulic drag of the converter I4 cannot causethe vehicle to creep. The hydraulic system further is such that thisband 33 is released during the time when the shaft I3 is shifted intoeither its reverse or forward low speed position. The clutching teeth 43thus need pick up only the frictional and inertia loads of the parts inthe gear set IE which happen to be revolving at the time, and the teethdo not pick up the full drag of the converter I4 under suchcircumstances. Due to the fact that the springs 52, 53 and 54 are usedfor applying the brake 33 while the motor 50 is utilized for disengagingthe brake, the vehicle may be parked in gear by engaging the teeth 43with either the teeth 46 or teeth 45 of the sun gears 30 and 21.Further, due to the fact that this band is applied by springs, thevehicle can be driven in low speed ratio even though the high-pressuresystem might fail from any cause. The relief valve 92 has theadvantageous function of not only regulating the pressure of fluiddischarged by the pump 81 and keeping it at a predetermined value, butthis valve also functions as an accumulator for fluid under pressure sothat when the valves I01, I88, and I09 are so controlled as to connectthe pump 81 and fluid motor 50, the fluid under pressure discharged bythe pump 81 is augmented by that contained in the relief valve 92 so asto give a quick disengagement of the friction brake 33. A smaller pump81 may be utilized for this quick disengagement than would otherwise berequired if no such accumulator were used.

We wish it to be understood that our invention is not to be limited tothe specific arrangements and constructions shown and described, exceptonly insofar as the claims may be so limited as it will be apparent tothose skilled in the art that changes may be made without departing fromthe principles of the invention. In particular, we wish it to beunderstood that in construing the following claims, wherever we mentiona friction engaging means or the like we mean to include by suchexpression not only a friction brake but also a friction clutch, a brakebeing understood to be an engaging means between a stationary part and amovable part and a clutch being understood to be an engaging means forcoupling together two movable parts. We also wish it to be understoodthat where in the following claims we mention means for operating abrake or an engaging means, we intend to include by this expression notonly means for disengaging such a brake or engaging means but also meansfor engaging such a brake or engaging means.

We claim:

1. In a transmission for an automobile vehicle, the combination of anaccelerator for the vehicle, drive shaft, a driven shaft, means forcompleting a power train between said shafts and including a gear setand a friction brake, spring means for engaging said brake, fluidpressure responsive means for disengaging said brake, a source of fluidpressure, a valve between said fluid pressure source and said fluidpressure responsive means, and linkage for connecting said valve andsaid accelerator and including a lever connected with said acceleratorand a lever connected with said valve, said levers being connected by apin and slot connection, said accelerator being operative through saidlinkage for moving said valve from one operative position connectingsaid fluid pressure source and said fluid pressure responsive means toanother position disconnecting said source and means and draining thefluid pressure responsive means to engage said friction brake when theaccelerator is moved from a closed throttle position toward an openthrottle position.

2. In a transmission, the combination of a drive shaft, a driven shaft,means for completing a power train between said shafts and including apositive type clutch and a friction type engaging means which when bothare engaged complete the power train,, spring means for engaging saidengaging means, fluid pressure responsive means for disengaging saidengaging means, a source of fluid pressure, and valve means between saidfluid pressure source and said fluid pressure responsive means forselectively applying fluid pressure to the fluid pressure responsivemeans or for draining the latter means.

3. In a transmission, the combination of a drive shaft, a driven shaft,means for completing a power train between said shafts and including apositive type clutch, a gear set, and a friction brake for an element ofsaid gear set, said power train completing means completing said powertrain when both the positive type clutch and the friction brake areengaged, spring means for applying said friction brake, fluid pressureresponsive means for disengaging said friction brake, a source of fluidpressure, and a valve between said fluid pressure source and said fluidpressure responsive means for selectively applying fluid pressure tosaid fluid pressure responsive means or for draining the latter means offluid.

4. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, means forcompleting a power train between said shafts and including a frictionengaging means, fluid pressure responsive means for operating saidengaging means, a source of fluid pressure, a valve between said fluidpressure source and said fluid pressure responsive means and operativelyconnected with said accelerator whereby to complete engagement of saidfriction engaging means when said accelerator is moved from a closedthrottle position to an open throttle position, a governor responsive tothe speed of said driven shaft, and a second valve in series with saidfirst valve and controlled by said governor whereby to block flow offluid between said first valve and said fluid pressure responsive meanswhen said accelerator is returned back to its said closed throttleposition and said driven shaft speed is above a predetermined value.

5. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, means forcompleting a power train between said shafts and including a gear setand a friction brake for an element of said gear set, spring means forapplying said brake, fluid pressure responsive means for disengagingsaid brake, a source of fluid pressure, a valve between said fluidpressure source and said fluid pressure responsive means and connectedwith said accelerator, said valve being moved from a position connectingsaid fluid pressure source with said fluid pressure responsive means toa position draining the latter means when said accelerator is moved froma closed throttle position toward an open throttle position, a governorresponsive to the speed of said driven shaft, a second valve betweensaid first valve and said fluid pressure responsive means, and meansconnecting said governor and said second-named valve whereby to movesaid second-named valve from a position connecting said first valve andsaid fluid pressure responsive means to a position disconnecting saidfirst valve and said fluid pressure responsive means when saidaccelerator is returned to its closed throttle position and the drivenshaft speed is above a predetermined value.

6. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, a gear sethaving neutral, low speed drive and high speed drive conditions, a shiftmember for changing the speed ratio of the gear set between its saidconditions and having a position corresponding to each of saidconditions, manual means operative on said member for shifting themember between its neutral and low speed drive positions, motor meansfor shifting said member between its low speed drive and its high speeddrive positions, and means connecting said motor means and saidaccelerator whereby the accelerator on being released to a closedthrottle position shifts said member to its high speed position from itslow speed position and the accelerator on being moved to an openthrottle position invariably causes shifting of said member from itshigh speed position to its low speed position.

7. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, a gear sethaving a neutral, a low speed drive and a high speed drive condition, amember for changing the speed ratio of said gear set between its saidconditions and having a position corresponding to each of saidconditions, manual means for shifting said member between its neutraland its low speed drive positions, motor means for shifting said memberbetween its low speed drive and its high speed drive positions, agovernor responsive to the speed of said driven shaft, and means underthe control of said accelerator and said governor for moving said shiftmember from its low speed drive to its high speed drive positions whenthe accelerator is released to a closed throttle position above apredetermined speed of said driven shaft, and means under the control ofsaid accelerator for moving said shift member from its high speedposition to its low speed position when the accelerator is moved to anopen throttle position.

8. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, a gear sethaving neutral, low speed drive and high speed drive conditions, a shiftmember for said gear set having positions corresponding to each of saidconditions, manual means for shifting said member between its neutraland its low speed drive positions, a friction engaging means forcompleting said low speed drive when engaged after said shift member hasbeen put into its low speed drive position, means under the control ofsaid accelerator for engaging said friction engaging means to completesaid low speed drive when the accelerator is moved from a closedthrottle position toward an open throttle posi-- tion, a governorresponsive to the speed of said driven shaft, motor means for shiftingsaid shift assent 19 mem er betw en its ow spee dr ve. n i h speed driveetit ons, m ns nde th ntfel of said accelerator and said governor foractur jtine Sa er means wh e to h f 'e i 'hii m mt r t low peed dri to is hi h speed dr os tions he ai aeeele etet' s moved to a closed throttleposition above a predetermin e of d d i ha an means ent he n r of d ee ee tor t e tueting said motor means whereby to shift said shift memberfrom its high speed drive to its low speed drive positions when theaccelerator is moved to an open throttle position.

9. In a transmission for an automotive vehie h ombi at o o a a l ator erthe vehi le a dr v the t a driven af e n for eem le 'ne a ow e d driveowe t i bet een Sai -shat er mean for om t n a h h ed driv PP Qi t a n.betwe n sa d ha ts spa l w p ed and aid i h. sp ed m a mp isin a shitt'me ber ha i a pos t on r po din 2 neut a and each f d s. i l lo s eedmean ioeludi s lso a icti n, n ag n means vh qh, h ga e c m e the lowspeed Power ain a e a h t m mb r ha c ei i iner l be n l t d in i speedpo io manua me ns. for h f ai hi mem e item t n ut a t ts lo e d, P immeter me ns t hit in sa sh member fro ts ow spe d to i h h eed P s oneans nd the control of said accelerator for engaging said frictionengaging means for completing the low speed power train when theaccelerator is moved from a closed throttle position toward an openthrottle position after said shift member has been shifted from itsneutral to its low speed position, and means under the control of saidaccelerator for actuating said motor means to shift said shift memberfrom its low speed to its high speed positions and to disengage saidfriction engaging means for shifting the transmission from low speedratio to high speed ratio when the acendear is returned to a closedthrottle position. ia t a m si n r n ootive vehicle the combination ofan accelerator for the vehiele, a drive shaft, a driven shaft, meansforcompleting a low speed drive between said shafts, m e tereemple ne a hih p ed e, be said sha ts hi mem o d n n the ra mi s o o its low peed r vv er he e e. pe at o the ren m es nin its high speed drive and having aneutral position and a position oorresponding to each of said drives,manual meansfor shifting said shiftmember from its neutral to its lowspeed position, said low speed drive means including a friction eneeeinm s wh ch when ed completes the raw speed drive after said shift memberhas been preliminarily moved to its low speed position, meansunder thecontrol of said accelerator forengaging said friction engaging meanswhen the accelerator is moved from a closed throttle position toward anopen throttle position with a df hitt m mbe e n in s o speed pe ition agovernor responsive to the speed of; said driven shaft, motor means forshifting said shift member from its low speed drive position to its highspeed drive position, and means under the controlof said accelerator andsaid governor for actuating said motormeans for shifting said shiftmember from its low speed drive to its high speed drive position and fordisengaging said friction engaging means when said accelerator isreturned to a closed throttle position. and the driven shaft is rotatingabove a predetermined speed.

11. In a transmission for an automotive vehi cle the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, means forproviding a low speed drive power train between said shafts, means forproviding a high speed drive power train between said shafts, a shiftmember for conditioning the transmission for said low speed drive andfor changing the speed ratio of the transmission into its high speeddrive and having a neutral position and a position for each of saiddrives, a friction engaging means for completing said low speed driveafter said shift member is placed in its low speed drive position tocondition the transmission for such drive, a governor responsive to thespeed of said driven shaft, manual means for shifting said shift mom,-ber'f'rom its neutral position to its low speed position, means underthe control of said accelerator for engaging said friction engagingmeans when the accelerator is moved from a closed throttle position toan open throttle posie tion, and means under the control of saidaccelerator and said governor for shifting said shift member from itslow speed position to. its high speed position and for disengaging saidfriction engaging means when said accelerator is returned from an openthrottle to itsclosed throttle posi: tion and the driven shaft speed isabove a pre-.- determined value.

12. In a transmission for an automotive vehicle the combination. of anaccelerator for the vehicle, a drive shaft, a driven shaft, means foproviding a low speed, drive between said shafts, means for providing.a, high speed drive between said shafts, a shift member for thetransmission having a neutral position, a lowspeed drive position and ahigh. speed drive position, means under the control of said acceleratorfor shiftin said shift member; from its, low speed drive 12,031- tionto. its high speed drive position when the accelerator is moved from anopen throttle. to a closed throttle position, means actuated by saidshift member for preventing a return of said shift member to itslowspeed drive position when the. accelerator is. thereafter moved out ofits said closed throttl os i n. toward an. open throttle position, andmea s. for overrul n said last-named means and bei n er the. c ntro ofsaid accelerator for changing the speed ratio of the transmission to alower speed drive and for movin sa d s ittmember om; s hie-h; driveposition to. its. low sp d. dr v po tion when the accelerator is movedinto a wideopen thr ttle kickd wn. po t nn a a smi si n or a a tom ive.ve i, the the Qmbine on. o an eee e t: or the vehicle, a drive shaft.driven shaft, mean for pr vidin a. low spee dr v bet en. a d hette,means. or pr v din a igh speed: r be ween aid, emits a ove nor re ponse. the eed of said driven shaft and having a switch which is c osed atepredete mined speed Qf, saidi ha t sw tchender he c r of Sa d. eeeeleraer and close a a, o d hro t tion of the. accelerator a shiftmemberforthe trans.- mi sien an havin low s e d o n ap'd a h pe d; po iion... ne r me ns or s f n said shift member and; being under thecontrol o sa d sw tches t e by: t he s ft. m ntber. te m. t ow r e te sis? eed. position. w en the; e eel retere m dt a l e d-th e le ei-t en ad. the ri n. sheit. s rotating; above apredeter pined: speed: a. w chactua d; v aid shirtrpemberandip pare elw hse ecee ereter switchwhereby... ta. overrule action he. as:

assent 21 celerator switch when the shift rail is in high speedposition, and another switch in series with said two first-namedswitches and adapted to overrule action of said third-named switchactuated by said shift member whereby to cause a shifting movement ofsaid shift member from its high speed position to its low speed positionwhen the accelerator is moved to a wide open throttle kickdown position,

14. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, means forproviding a low speed drive between said shafts, means for providing ahigh speed drive between said shafts, a selector for conditioning thetransmission either for a drive only in low speed ratio or for a drivein either low speed ratio or high speed ratio, a friction engaging meansfor completing a drive through the transmission in low speed ratio,fluid pressure means for operating said friction engaging means, asource of fluid pressure, three valves between said fluid pressuresource and said fluid pressure responsive means, and a governorresponsive to the speed of said driven shaft, one of said valves beingactuated by said accelerator, another of said valves being actuated bysaid governor and the third of said valves being actuated by saidselector, said accelerator actuated valve functioning to completeengagement of said friction engaging means when the accelerator is movedfrom a closed throttle position toward an open throttle position whenthe governor actuated valve is in a position corresponding to a lowspeed of said driven shaft, said governor actuated valve maintainingsaid friction engaging means disengaged when the valve is in a positioncorresponding to a high speed of said driven shaft, and said selectoroperated valve cooperating with said governor actuated valve formaintaining the friction engaging means disengaged for a high speed ofsaid driven shaft when the selector is set for its high speed ratioposition and being ineffective for such maintenance of condition of saidfriction engaging means when in its position corresponding to low speedratio setting of said selector.

15. In a transmission for an automotive vehicle, the combination of anaccelerator for the vehicle, a drive shaft, a driven shaft, means forproviding a low speed drive between said shafts, means for providing ahigh speed drive between said shafts, a shift member for conditioningthe transmission for low speed drive or for changing the speed ratio ofthe transmission into high speed drive and having a neutral, a low speeddrive and a high speed drive position, a selector effective for shiftingthe shift member between its neutral and its low speed drive positions,motor means for shifting the shift member between its low speed driveand its high speed drive positions, a friction engaging means forcompleting said low speed drive after said shift member is preliminarilyput in its low speed drive position, a governor responsive to the speedof said driven shaft, fluid pressure responsive means for actuating saidfriction engaging means, a source of fluid pressure, and three valvesbetween said fluid pressure source and .said fluid pressure responsivemeans for said engaging means, one of said valves being actuated by saidaccelerator to be moved when the accelerator is moved out of a closedthrottle position toward an open throttle position, an-

other of said valves being responsive to said governor and to saidaccelerator and being moved from one position to another when theaccelerator is in a closed throttle position and the driven shaft isabove a predetermined speed, and the third of said valves being actuatedby said selector to be moved when the selector is moved from a low speedlock-up position to an automatic high position, means under the controlof said accelerator and said governor for shifting said shift memberfrom its low speed position to its high speed position when theaccelerator is moved to a closed throttle position and said driven shaftis rotating above a predetermined speed, said accelerator actuated valvefunctioning to engage said friction engaging means when the acceleratoris moved from a closed throttle position toward an open throttleposition when the driven shaft is rotating at a low speed, the governoractuated valve functioning to maintain said friction engaging meansdisengaged regardless of the movement of the accelerator when theselector actuated valve is set with the selector being in automatic highposition, and the selector actuating valve functioning to prevent suchmaintenance of engagement of said friction engaging means when the valveis set by the selector when the latter is in its low speed driveposition.

16. In a transmission, the combination of a drive shaft, a driven shaft,a hydrodynamic torque transmitting device and fluid pressure operatedmeans for completing a drive through the torque transmitting device andbetween said shafts, a pump for supplying fluid under pressure to saidfluid operated means, a relief valve for maintaining said fluid pressureapplied to said fluid pressure operated means at a substantiallyconstant value, said relief valve comprising a piston slidable in acylinder and acted on by a spring, said cylinder having a dischargeopening in its walls which is opened by said piston when the pistonmoves a distance against said spring, said discharge opening beingconnected with said hydrodynamic device for supplying fluid thereto, anda second relief valve similar to said first relief valve and including apiston movable against a spring within a cylinder and having a dischargeopening, said last-named piston being effected by the pressure of fluiddischarged from said first relief valve so that the second-named reliefvalve regulates the pressure within the hydrodynamic device, a fluidtank connected with the intake side of said pressure pump, and ascavenger pump connected with the casing of said transmission fordrawing out of said casing any fluid leaking from said hydrodynamicdevice and discharging it into said fluid tank.

PALMER ORR. CLIFFORD L. SWIFT.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date Re. 23,326 Fleischel Jan. 9, 1951 1,609,782 Small et a1. Dec.7, 1926 1,673,863 Brown et a1 June 19, 1928 1,839,145 Forichon Dec. 29,1931 2,008,231 Vincent July 16, 1935 2,009,477 Clayton July 30, 19352,068,579 Tatter Jan. 19, 1937 2,081,527 Breese May 25, 1937 2,152,089Price et a1 Mar. 28, 1939 (Other references on following page) UNITEDSTATES PATENT Number Name Date Patterson Sept. 19, 1939 Hale Aug. 6,1940 r Carnegie Nov. 12, 1940 Stortz Dec. 31, 1940 Clayton May 5, 1942Dolza May 12, 1942 Russell Oct. 13, 1942 10 Cotterman May 18, 1943 Nuttet a1 Oct. 26, 1943 Cotterman Mar. 14, 1944 Number Number Name DateSimpson Feb. 6, 1945 Dodge Apr. 3, 1945 Osborne Apr. 24, 1945 LaBrieSept. 10, 1946 Greenlee July 25, 1950 Weiss et a1 Feb. 13, 1951 FOREIGNPATENTS Country Date Great Britain July 1, 1921 Great Britain May 7,1931 France Oct. 26, 1921

